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arXiv · 1907.12729

MPGD simulation in negative-ion gas for direction-sensitive dark matter searches

Abstract

Negative-ion time projection chambers (NITPCs) provide the absolute z-position from the arrival-times' difference of several species of negative-ions. This is a strong background reduction method for rare event searches, such as direct dark mater searches. The characteristics of micro pattern gaseous detectors (MPGDs) in negative-ion gas were studied by both experiments and simulations to develop an NITPC for dark matter search experiments. An MPGD simulation method for the negative-ion gas with Garfield++, which has not yet been established, was developed. We present herein the MPGD simulation results in negative-ion gas, $\mathrm{SF_{6}}$ gas, together with the experimental results, such as gain, energy resolution, and signal creation from the MPGD for future NITPC optimization.

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Hirohisa Ishiura, Rob Veenhof, Kentaro Miuchi, Ikeda Tomonori. 2019-07-30. MPGD simulation in negative-ion gas for direction-sensitive dark matter searches. https://doi.org/10.1088/1742-6596%2F1498%2F1%2F012018

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